Gear shifter means



Patented Dec. 3, 1940 UNITED I STATES #PATENT ortica 3 Claims.

This application relates to gear shifter means and positive lock arrangements for the same, and is illustrated in conjunctionv with a power take-off mechanism useful with motor vehicle transmissions.

The prior art contains power take-off mechanisms useful with motor vehicletransmissions. In these mechanisms, there is provided a manually operable means for shifting the gear thereof, and in this applicationl disclose a novel gear shifter arrangementJ for shifting the gear of a power take-off mechanism, and I also show a novel positive lock arrangement `for the gear shifter means, whereby the gear will be locked in any indexed position against shifting.

For an understanding of the mechanism herein disclosed, reference should be had to the appended drawing. In this drawing, Y

Figure 1 illustrates a vpower take-off mechanism employing my novel gear shifter means and positive lock arrangement.

Figures 2 and 3 are fragmentary cross sections on corresponding lines of Figure l.

Figures 4-6 show a part of the means.

A motor vehicle transmission consists of a casing within which are gears and which has an opening in one side thereof adaptedto be aligned with an opening I4 in a casing I5 of a power take-off mechanism. Suitably supported in bearings of the casing I5 is a power take-01T shaft I6 upon which is slidably and nonrotatably mounted, as by means of a key I1, a gear I8 which may be shifted along the shaft I6 so as to occupy a neutral position between the gears of the transmission or to be engaged selectively with such gears.

For sliding the gear I8 left and right on its shaft I6 there is provided the novel gear shifter means and positive lock arrangement of this application. Ihis arrangement includes a gear shifter means 2l) in the form of a round hollow rod having its shank slidably disposed in the slideway 2i of the casing I5. The free or exposed end 22 of the rod 20 is provided with a cross slot 23 in which; may be disposed the peripheral edge of the gear I8 whereby, when the rod 2i) is shifted left and right in its slideway 2|, it will cause the gear I8 to slide left and right on its keyway II.

The rod is provided with three additional separate and distinct slots. An upper slot 24 extends from the left end 22 of the rod to a point approximately midway between the ends of the rod and the slot 24 is deep enough so as to extend to the base of slot 23. A lower slot 25 of a depth to reach` the base ofY the slot 24 extends from the' cross slot 23 to the small end of the rod 20. In such small end is a transverse end slot 23. y

Disposed within slots 24-25-26 of the rod is 5 a cam in the form of a at bar 21 which'is bent so that a part ofit lies within the upper slot 24 and a part lies within the lower slot 25. The left end of the bar, projecting beyond the end 22 of the rod 26, is secured as at 28 to a push- 10 pull Bowden wire 29 terminating in a handle which may be at any convenient point of the vehicle. The right end of the bar 21 is bent to provide a key 3i which projects through the upper portion of the end slot 26 of the rod and 15 seats in a groove or keyway 32 in the upper wall of the slideway 2l whereby relative rotation of the assembly of the rod and bar with respect to the casing I5 will be prevented, without however Ainterfering with relative longitudinal movement 20 of that assembly with respect to the casing.

Formed in the casing I5 is a recess 35 containing a coiled compression spring 36 reacting against a ball detent 31 adapted to be projected into a selected one of three holes 38 formedin 25 the rod 20 at slot 25 and projecting radially from the lower surface thereof, co-axially with the Vlower slot 25. For controlling the ball detent 31 there are provided three hill and valley notches 39 in the lower edge of the cam 2'I.

The use and operation of the gear shifter means and positive lock arrangement is as follows: Assume the parts to be in the neutral position of Figure 1. Ball detent 31 is in the center hole 38 to lock the rod and gear against shift- 35 ing and is aligned with the center notch 39 of the cam. Key 3i is spaced from the left end of slot 26. Rod 26 and the enlarged end 28 of cam 2l is spaced from the end 22 of the rod. Movement of the cam 2l in either direction from its 40 neutral position will rst cause the ball detent 3l to be biased downwardly and out of center hole 38 of the shifter rod to unlock that shifter rod and permit it to slide with respect to the casing, due to the later engagement between the cam and the shifter rod, caused by engagement of either key 3l or end 28 of the cam with the end of the rod, lost motion travel being determined by the distance between key 3| and the left end of slot 26 of the rod and between cam 50 end 28 and rod end 22,

When the rod is moved by the cam, shortly after the cam had released the rod from the detent, a different hole 38 of the rod will align with the detent and thereupon the detentwill be urged into such hole once more to lock the rod against sliding with respect to that casing.

It will be observed that the parts are so disposed that when the detent 31 is within a valley notch 39 of the cam one half of the detent is within the hole 38 of the rod and the other half of the detent is still Within the hole 35 of the casing I5 and thus the rod and casing are interlocked against relative movement. On the other hand when a hill of the cam 21 aligns with the detent 31, it will force the detent back into the hole 35 and no part of the detent will be Within a hole 38 of the rod and .thus the rod will be free to slide with respect to the casing.

It will also be observed that by a simple push or pull movement on the Bowden wire 29 the rod is unlocked from the casing rst and then moved longitudinally, and then again automatically locked to the casing by the detent. A time delay between each pair of these steps is provided by the lost motion spacing between the ends of cam 21 and the engaged parts of the rod 20.

Now having described the gear shifter and positive lock arrangement herein described reference may be had to the claims which follow for a determination of the invention. I` claim:

1. A gear shifter and positive lock arrangement therefor comp-rising a gear to be shifted axially, gear shifter means connected to the gear and adapted to be moved longitudinally, for moving the gear axially, for shifting, a detent for said means, a spring for biasing said detent into locking position with respect to said means, a cam for moving said detent out of such locking position, and for releasing said detent so that the spring can move it into locking position,`and means for moving said cam longitudinally to and from its detent controlling positions, the gear shifter means and the cam having a positive lost motion interlocking connection formed by transverse projections on the ends of the cam for engaging the gear shifter means and moving it longitudinally wherebyV movement of the cam, when the detent is in locking position, irst moves the detent out of locking position, without then moving the means, and later moves the means for shifting the gear, and then releases the detent so that it can be moved into locking position by the' spring.

2. A gear shifter and positive lock arrangement therefor comprising a gear to be shifted axially, a hollow rod connected to the gear and adapted to be moved longitudinally, for moving the gear axially, for shifting, a detent forv said rod, a spring lfor biasing said detent into locking position with respect to said rod, a cam consisting of a bar slidably mounted Within said rod for moving said detent out of such locking posi-f tion, and for releasing said detent so that the spring can move it into locking position, and means for moving' said cam to and from its detent controlling positions, the rod and the bar having a longitudinally lost motion interlocking connection formed by transverse projections on the ends of the bar to engage and move the rod longitudinally whereby movement of the bar, when the detent is in locking position, first moves the detent out of locking position, without then moving the rod, and later moves the rod for shifting the gear, and then releases the detent so that it can be moved to locking position by the spring. Y l

3. A gear shifter and positive lock arrangement therefor comprising-a gear to be shifted axially, a hollow rod connected to the gear and adapted to be moved longitudinally, for moving the gear axially, for shifting, a' detent for said rod,` a

spring for biasing vsaid detent into locking posi-y tion with respect to said rod, said rod havingV holes for receiving said detent, a cam consisting of a bar slidablymounted Within said rod and formed with hill and valley notches in an edge thereof for moving said detent out of such locking position, and for releasing said detent so that the spring can move it' into locking posi-- tion, and means for lmoving said cam to and from its detent controlling positions, the rod and the bar having a positive lost motion interlocking connection formedv by transverse projections on the ends of the bar to engage and move the rod longitudinally whereby movement of the bar, when the detent4 is in locking position, firstmoves the detent out of locking position, Without then moving the rod, and later moves the'rod for shift- 

